Recently, three-dimensional display techniques are rapidly developed, and becomes a hot research spot. The three-dimensional display technique is importantly used in the fields of medical treatment, advertisement, military affairs, exhibit, recreation, etc. For the original three-dimensional display technique, a stereoscopic image is mainly observed via wearing special spectacles. However, currently popular products are mainly naked-eye three-dimensional display units based on binocular parallax. The main design of the naked eye three-dimensional display unit is to set a grating before a display panel, wherein the grating respectively provides at least two parallax images displayed by a display panel to left eye and right eye of an observer.
Presently, most naked-eye three-dimensional display units can only display the contents in the form of three dimensions. However, there is no mutual effect between the observer and the displaying contents, and the effect in the real living is not completely exhibited.
Referring to FIGS. 1A and 1B, when a position of an observer 103 changes, a moving direction and speed of an ambient object observed may generate difference, and a sheltering state may also change. This difference and change is referred to as movement parallax. Firstly, referring to FIG. 1A, a scene observed by the observer 103 is an image of an object 101 partly sheltered by an object 102. When the observer 103 moves to a position shown in FIG. 1B, an image that no sheltering relation occurs between the object 102 and the object 101 is observed.
The movement parallax may cause the observer 103 to have a certain depth feeling. With the movement of the observer 103, a feeling of spatial arrangement between objects may be enhanced due to changing of relative movement and sheltering relation between the objects. For example, when only observing from FIG. 1A, the observer 103 may not feel that there is a longer distance between the object 101 and the object 102. However, when the observer 103 moves to the position shown in FIG. 1B, a distance between the two objects is reflected.